Conduct a Chart A inventory of equipment
is permitted only with specific NAVAIR (AIR-5222)
approval, a hydrometer will not normally be a part of
actually installed in the aircraft. This inventory will be
the weighing kit.
accomplished under the supervision of the qualified
weight and balance technician (qualified by graduation
Weighing Procedure
from one of the NADEP weight and balance schools)
responsible for weighing aircraft. A basic weight
A defined and orderly aircraft weighing procedure
without the correct associate inventory is of no value.
lessens the chance of omitting necessary dimensional
Correct the Chart C, Basic Weight and Balance
or scale readings. The choice of alternative procedures
Record, DD Form 365-3, based upon the Chart A
depends upon the equipment at hand and on the
inventory. Use such data as the current Chart C basic
circumstances under which the aircraft is to be
weight, the Chart A inventory, and the Chart E loading
weighed. Always refer to the particular aircraft's Chart
data to estimate an "as weighed" weight and moment.
E loading data. Use the following procedures to
To the current basic weight, add the oil (if not part of
accomplish proper aircraft weighing.
current basic weight) and "items weighed but not part
Thoroughly clean the aircraft inside and out,
of the current basic weight," and subtract the "items in
removing dirt, grease, and moisture. Allow the aircraft
the basic weight but not in the aircraft."
sufficient time to dry before weighing. Assemble the
When weighing an aircraft with platform scales,
required weighing equipment, including scales,
such as the MEWS or stationary scales, ensure that all
hoisting equipment, jacks, cribbing, leveling bars,
scales are within their calibration date. If the scales are
level, measuring tape, plumb bobs, and chalk line.
portable, set up the scales and level them. Attach the
Drain fuel in accordance with the aircraft's Chart E or
cables from the platform to the readout. Warm up
other applicable instructions. This draining is generally
electronic scales for a minimum of 20 minutes. Zero the
done in the aircraft's normal ground attitude. Aircraft
scales. Level the aircraft by servicing. Most aircraft can
with internal foam in their fuel tanks pose special
be leveled in this manner. See NAVAIR 01-1B-40 and
problems, since some fuel is always retained in the
NAVAIR 01-1B-50 for aircraft where this procedure is
foam. In this case, unless specific instructions are in the
not required or desired.
aircraft's Chart E, draining should be terminated when
the fuel flow becomes discontinuous or starts to drip.
Tow the aircraft onto the scales. Do not apply the
Remove load items, such as bombs,
aircraft's brakes, because they may bind the scales; this
would require rezeroing of the scales. Recheck the
ammunition, cargo, crew members, and equipment not
aircraft level. Read the scales and make dimensional
having a fixed position in the aircraft. They are not
measurements per Chart E instructions and NAVAIR
listed as a part of the basic weight on the Chart A, Basic
01-1B-50.
Weight Checklist Record, DD Form 365A (DD Form
365-1), and should not be in the aircraft when weighed.
Make the applicable DD Form 365-2 entries and
Check all reservoirs and tanks for liquids, such as
verify the weighing results. If a large discrepancy is
drinking and washing water, hydraulic fluid, anti-icing
noted, check to see where the error could have
fluid, cooling fluids, and liquid oxygen. Reservoirs and
occurred. If the source of the error is not found, reweigh
tanks should be empty or filled to normal capacity
aircraft by removing and replacing the aircraft on the
before weighing. Oil tanks are to be filled to normal
scales.
capacity before weighing. Calculations on the Aircraft
Remove the aircraft from the scales. If the scale
Weighing Record, DD Form 365-2, will resolve
does not return to zero after 10 minutes, reweigh the
differences between the as-weighed condition and the
aircraft. Be sure that the brakes are not used or applied.
basic-weight condition. All waste tanks must be empty.
Determine the tare per the appropriate scale
Move the aircraft to the area where it will be
instructions. Tare is the weight of equipment necessary
weighed. Do not set the aircraft brakes, for this may
for weighing the aircraft. Tare includes items such as
induce side loads and thrust loads on the scales, which,
shocks, blocks, slings, and jacks. These items are
in turn, may give erroneous weighing results. The
included in the scale reading, but are not part of the
aircraft must be weighed in a closed hangar or building
aircraft weight. Tare may also include a scale correction
with no blowers or ventilating system blowing air upon
factor. A scale correction factor is used to modify scale
the aircraft.
readings because of inherent inaccuracies of the scale.
If the scale correction factor is larger than the scale
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